Diversification:
This sounds contradictory to the description given by takata here. The manual says that if the ADR is disconnected, it turns off both the pitot probes and the AoA probes ("incidence probes"). So something is inaccurate here?
I think I found the error, reading
this interesting writeup about handling of unreliable airspeed. Quote:
The BUSS comes with a new ADIUR standar (among other new system standards), where the AOA information is provided through the IRs and not through the ADRs. This enables selecting all ADRs off without losing the STALL WARNING PROTECTION.
The AOA information provides a guidance area in place of the speed scale. When the crew selects all ADRs OFF, then:
- The Back-Up Speed Scale replaces the PFD speed scale on both PFDs,
- GPS Altitude replaces the Altitude Scale on both PFDs.
The Back-Up Speed Scale then enables to fly at a safe speed, i. e. above stall speeds, by adjusting thrust and pitch.
So based on this, the BUSS system in fact uses inertial data based AoA information, and not the AoA probe data. This is now consistent with the information provided by takata.